blob: 241317239ffcf45a8a5fa5fdf3db54ce0a271a1e [file] [log] [blame]
# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
# Copyright 2021 ARM Ltd.
%YAML 1.2
---
$id: http://devicetree.org/schemas/firmware/arm,scpi.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: System Control and Power Interface (SCPI) Message Protocol
maintainers:
- Sudeep Holla <sudeep.holla@arm.com>
description: |
Firmware implementing the SCPI described in ARM document number ARM DUI
0922B ("ARM Compute Subsystem SCP: Message Interface Protocols")[0] can be
used by Linux to initiate various system control and power operations.
This binding is intended to define the interface the firmware implementing
the SCPI provide for OSPM in the device tree.
[0] http://infocenter.arm.com/help/topic/com.arm.doc.dui0922b/index.html
properties:
$nodename:
const: scpi
compatible:
description:
SCPI compliant firmware complying to SCPI v1.0 and above OR
SCPI compliant firmware complying to all unversioned releases
prior to SCPI v1.0
oneOf:
- const: arm,scpi # SCPI v1.0 and above
- const: arm,scpi-pre-1.0 # Unversioned SCPI before v1.0
- items:
- enum:
- amlogic,meson-gxbb-scpi
- const: arm,scpi-pre-1.0
mboxes:
description:
List of phandle and mailbox channel specifiers. All the channels reserved
by remote SCP firmware for use by SCPI message protocol should be
specified in any order.
minItems: 1
maxItems: 4
shmem:
description:
List of phandle pointing to the shared memory(SHM) area between the
processors using these mailboxes for IPC, one for each mailbox SHM can
be any memory reserved for the purpose of this communication between the
processors.
minItems: 1
maxItems: 4
power-controller:
type: object
description:
This sub-node represents SCPI power domain controller.
properties:
compatible:
const: arm,scpi-power-domains
'#power-domain-cells':
const: 1
num-domains:
$ref: /schemas/types.yaml#/definitions/uint32
description:
Total number of power domains provided by SCPI. This is needed as
the SCPI message protocol lacks a mechanism to query this
information at runtime.
required:
- compatible
- '#power-domain-cells'
- num-domains
additionalProperties: false
sensors:
type: object
description: |
This sub-node represents SCPI sensors controller.
properties:
compatible:
oneOf:
- const: arm,scpi-sensors
- items:
- enum:
- amlogic,meson-gxbb-scpi-sensors
- const: arm,scpi-sensors
'#thermal-sensor-cells':
const: 1
required:
- compatible
- '#thermal-sensor-cells'
additionalProperties: false
clocks:
type: object
description:
This is the container node. Each sub-node represents one of the types
of clock controller - indexed or full range.
properties:
compatible:
const: arm,scpi-clocks
patternProperties:
"^clocks-[0-9a-f]+$":
type: object
description: |
This sub-node represents one of the types of clock controller
- indexed or full range.
"arm,scpi-dvfs-clocks" - all the clocks that are variable and index
based. These clocks don't provide an entire range of values between
the limits but only discrete points within the range. The firmware
provides the mapping for each such operating frequency and the index
associated with it. The firmware also manages the voltage scaling
appropriately with the clock scaling.
"arm,scpi-variable-clocks" - all the clocks that are variable and
provide full range within the specified range. The firmware provides
the range of values within a specified range.
properties:
compatible:
enum:
- arm,scpi-dvfs-clocks
- arm,scpi-variable-clocks
'#clock-cells':
const: 1
clock-output-names: true
clock-indices:
$ref: /schemas/types.yaml#/definitions/uint32-array
description:
The identifying number for the clocks(i.e.clock_id) in the node.
It can be non linear and hence provide the mapping of identifiers
into the clock-output-names array.
required:
- compatible
- '#clock-cells'
- clock-output-names
- clock-indices
additionalProperties: false
required:
- compatible
additionalProperties: false
additionalProperties: false
required:
- compatible
- mboxes
- shmem
examples:
- |
firmware {
scpi {
compatible = "arm,scpi";
mboxes = <&mhuA 1>;
shmem = <&cpu_scp_hpri>; /* HP-NonSecure */
scpi_devpd: power-controller {
compatible = "arm,scpi-power-domains";
num-domains = <2>;
#power-domain-cells = <1>;
};
clocks {
compatible = "arm,scpi-clocks";
scpi_dvfs: clocks-0 {
compatible = "arm,scpi-dvfs-clocks";
#clock-cells = <1>;
clock-indices = <0>, <1>, <2>;
clock-output-names = "atlclk", "aplclk","gpuclk";
};
scpi_clk: clocks-1 {
compatible = "arm,scpi-variable-clocks";
#clock-cells = <1>;
clock-indices = <3>, <4>;
clock-output-names = "pxlclk0", "pxlclk1";
};
};
scpi_sensors: sensors {
compatible = "arm,scpi-sensors";
#thermal-sensor-cells = <1>;
};
};
};
soc {
#address-cells = <2>;
#size-cells = <2>;
sram@50000000 {
compatible = "mmio-sram";
reg = <0x0 0x50000000 0x0 0x10000>;
#address-cells = <1>;
#size-cells = <1>;
ranges = <0 0x0 0x50000000 0x10000>;
cpu_scp_lpri: scp-sram-section@0 {
compatible = "arm,scp-shmem";
reg = <0x0 0x200>;
};
cpu_scp_hpri: scp-sram-section@200 {
compatible = "arm,scp-shmem";
reg = <0x200 0x200>;
};
};
};
- |
firmware {
scpi {
compatible = "amlogic,meson-gxbb-scpi", "arm,scpi-pre-1.0";
mboxes = <&mailbox 1>, <&mailbox 2>;
shmem = <&cpu_scp_lpri>, <&cpu_scp_hpri>;
scpi_sensors1: sensors {
compatible = "amlogic,meson-gxbb-scpi-sensors", "arm,scpi-sensors";
#thermal-sensor-cells = <1>;
};
};
};
...